Method of inhibiting fibrosis with a somatostatin agonist

ABSTRACT

The present invention relates to a method of inhibiting fibrosis in a patient. The method comprises administering a therapeutically effective amount of a somatostatin, a somatostatin agonist or a pharmaceutically acceptable salt thereof to said patent.

This application is a divisional of Ser. No. 09/254,097, filed May 10,1999, now U.S. Pat. No. 6,268,342, which is a 371 of PCT/US97/14154,filed Aug. 27, 1997, which is a continuation-in-part of Ser. No.08/705,790, filed Aug. 30, 1996, now abandoned.

BACKGROUND OF THE INVENTION

Tissue comprises organized cellular groups that are attached to anextracellular matrix and are surrounded by a network of blood vessels.Fibrosis is an abnormal accumulation of a collagen matrix followinginjury or inflammation which alters the structure and function ofvarious tissues. Irrespective of location, the major pathology offibrosis involves an excessive deposition of a collagen matrix whichreplaces the normal tissue at that site. Progressive fibrosis in thekidney, liver, lung, heart, bone or bone marrow, and skin is a majorcause of death and suffering. See, e.g., Border, et al., New Engl. J.Med. 331:1286 (1994).

Development of fibrosis has been linked to the overexpression andover-production of TGF-β in numerous tissues and fibrotic disease states(see Border et al., N Engl J Med 1994, pp. 1286-92).

SUMMARY OF THE INVENTION

The present Invention relates to a method of treating fibrosis in apatient (e.g., a mammal such as a human). The method includes the stepof administering a therapeutically effective amount of somatostatin or asomatostatin agonist to said patient. The somatostatin or somatostatinagonist may be administered orally, topically, parenterally, e.g.,administered intravenously, subcutaneously, or by implantation of asustained release formulation. Fibrosis is the abnormal accumulation ofan extracellular matrix (e.g., collagen) in tissue. The fibrosis, forexample, may be located: in the kidney, for example, fibrosis asobserved in glomerulonenephritis, diabetic nephropathy), allograftrejection, and HIV nephropathy; in the liver, for example, cirrhosis,and veno-occlusive disease; in the lung, for example, idiopathicfibrosis; in the skin, for example, systemic sclerosis, keloids, scars,and eosinophilia-myalgia syndrome; in the central nervous system, forexample, intraocular fibrosis; in the cardiovascular system, forexample, vascular restenosis; in the nose, for example, nasal polyposis;in bone or bone marrow; in an endocrine organ; and in thegastrointestinal system.

A fibrotic disorder may be induced by a number of causes including:chemotherapy, for example pulmonary fibrosis resulting from bleomycin,chlorambucil, cyclophsphamide, methotrexate, mustine, or procarbazinetreatment; radiation exposure whether accidental or purposeful as inradiation therapy, for example, interstitial lung disease (ILD)resulting from radiation; environmental or industrial factors orpollutants such as chemicals, fumes, metals, vapors, gases, etc. (e.g.ILD resulting from asbestos or coal dust); a drug or combination ofdrugs, for example, antibiotics (e.g. penicillins, sulfonamides, etc.),cardiovascular drugs (e.g. hydralazine, beta blockers, etc.), CNS drugs(phenytoin, chlorpromazine, etc.) anti-inflammatory drugs (e.g. goldsalts, phenylbutazone, etc.), etc. can cause ILD; an immune reactiondisorder, for example, chronic graft-vs-host disease with dermalfibrosis); disease states (e.g., aspiration pneumonia which is a knowncause of ILD) which include parasite induced fibrosis; and wounds, forexample, blunt trauma, surgical incisions, battlefield wounds, etc., asin penetrating injuries of the CNS.

In one aspect, this invention provides a method of inhibiting fibrosisin a patient, said method comprising administering a therapeuticallyeffective amount of somatostatin or a somatostatin agonist to saidpatient; a method which is preferred of the foregoing method is whereinsaid method comprises administering a therapeutically effective amountof a somatostatin agonist to said patient.

In another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis which is inhibited is in the:

kidney wherein the fibrotic disorder inhibited in the kidney ispreferably glomerulonephritis, diabetic nephropathy, allograft rejectionor HIV nephropathy,

lung wherein the fibrotic disorder inhibited in the lung is preferablyidiopathic fibrosis or autoimmune fibrosis,

liver wherein the fibrotic disorder inhibited in the liver is preferablycirrhosis or veno-occlusive disease,

skin wherein the fibrotic disorder inhibited in the skin is preferablysystemic sclerosis, keloids, scars or eosinophilia-myalgia syndrome,

central nervous system wherein the fibrotic disorder inhibited in thecentral nervous system is preferably intraocular fibrosis,

bone or bone marrow, cardiovascular system, an endocrine organ orgastrointestinal system. Each of the immediately foregoing methods ispreferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by chemotherapy and preferably the fibrosisinhibited is in the kidney, lung, liver, skin, central nervous system,bone or bone marrow, cardiovascular system, an endocrine organ orgastrointestinal system. Each of the immediately foregoing methods ispreferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by radiation and preferably the fibrosis inhibitedis in the kidney, lung, liver, skin, central nervous system, bone orbone marrow, cardiovascular system, an endocrine organ orgastrointestinal system. Each of the immediately foregoing methods ispreferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by a drug or combination of drugs and preferably thefibrosis inhibited is in the kidney, lung, liver, skin, central nervoussystem, bone or bone marrow, cardiovascular system, an endocrine organor gastrointestinal system. Each of the immediately foregoing methods ispreferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by a disease state and preferably the fibrosisinhibited is in the kidney, lung, liver, skin, central nervous system,bone or bone marrow, cardiovascular system, an endocrine organ orgastrointestinal system. Each of the immediately foregoing methods ispreferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by an environmental or industrial factor andpreferably the fibrosis inhibited is in the kidney, lung, liver, skin,central nervous system, bone or bone marrow, cardiovascular system, anendocrine organ or gastrointestinal system. Each of the immediatelyforegoing methods is preferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by an immune response by the patient and preferablythe fibrosis inhibited is in the kidney, lung, liver, skin, centralnervous system, bone or bone marrow, cardiovascular system, an endocrineorgan or gastrointestinal system. Each of the immediately foregoingmethods is preferred.

In yet another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thefibrosis is induced by a wound and preferably the fibrosis inhibited isin the kidney, lung, liver, skin, central nervous system, bone or bonemarrow, cardiovascular system, an endocrine organ or gastrointestinalsystem. Each of the immediately foregoing methods is preferred.

In still another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thesomatostatin agonist has a higher binding affinity for humansomatostatin sub-type receptor 1 than the other human somatostatinsub-type receptors, for human somatostatin sub-type receptor 2 than theother human somatostatin sub-type receptors, for human somatostatinsub-type receptor 3 than the other human somatostatin sub-type receptorsfor human somatostatin sub-type receptor 4 than the other humansomatostatin sub-type receptors, or for human somatostatin sub-typereceptor 5 than the other human somatostatin sub-type receptors; orwherein the somatostatin agonist has a higher binding affinity for twoor more of human somatostatin receptor sub-types e.g., 1, 2, 3, 4-and/or 5. Each of the immediately forgoing methods is preferred.

In still another aspect, this invention provides a method of inhibitingfibrosis in a patient which comprises administering to the patient atherapeutically effective amount of a somatostatin agonist wherein thesomatostatin agonist is

or a pharmaceutically acceptable salt thereof, wherein

A¹ is a D- or L- isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, β-Nal,β-Pal, Trp, Phe, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, or o-X-Phe;

A² is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or p-X-Phe;

A³ is pyridyl-Ala, Trp, Phe, β-Nal, 2,4-dichloro-Phe, pentafluoro-Phe,o-X-Phe, or p-X-Phe;

A⁶ is Val, Ala, Leu, Ile, Nle, Thr, Abu, or Ser;

A⁷ is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or p-X-Phe;

A⁸ is a D- or L-isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, Phe, β-Nal,pyridyl-Ala, Trp, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, oro-X-Phe;

wherein X for each occurrence is independently selected from the groupconsisting of CH₃, Cl, Br, F, OH, OCH₃ and NO₂;

each R₁ and R₂, independently, is H, lower acyl or lower alkyl; and R₃is OH or NH₂; provided that at least one of A¹ and A⁸ and one of A² andA⁷ must be an aromatic amino acid; and further provided that A¹, A², A⁷and A⁸ cannot all be aromatic amino acids.

In still another aspect, a method of inhibiting fibrosis in a patientwhich comprises administering to the patient a therapeutically effectiveamount of a somatostatin agonist wherein the somatostatin agonist is

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-p-NO₂-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Nal-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂; or

H-D-Phe-Ala-Tyr-D-Trp-Lys-Val-Ala-β-D-Nal-NH₂ or a pharmaceuticallyacceptable salt thereof.

In still another aspect, a method of inhibiting fibrosis in a patientwhich comprises administering to the patient a therapeutically effectiveamount of a somatostatin agonist wherein the somatostatin agonist is

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-β-Nal-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-OH;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

Gly-Pen-Phe-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Tyr-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-ol;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Trp-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Trp-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Ac-D-Phe-Lys*-Tyr-D-Trp-Lys-Val-Asp-Thr-NH₂, wherein an amide bridge isbetween Lys* and Asp;

Ac-hArg (Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Bu)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-H₂;

Ac-L-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-L-hArg(CH₂-CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NHEt;

Ac-hArg(CH₃, hexyl)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-hArg(hexyl)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Propionyl-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys(iPr)-Thr-Cys-Thr-NH₂;

Ac-D-β-Nal-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Gly-hArg(Et)₂-NH₂;

Ac-D-Lys(iPr)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(Et)₂-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-Cys-Lys-Asn-4-Cl-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Ser-D-Cys-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-p-Cl-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-β-Nal-NH₂;

H-pentafluoro-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Ac-D-β-Nal-Cys-pentafluoro-Phe-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

Ac-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-β-Nal-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Cys-Thr-NH₂;

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-N-Me-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-Phe)

cyclo (Pro-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Ser-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-p-Cl-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-D-Lys-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-Lys-D-Trp-D-Phe);

cyclo (D-Abu-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Tyr);

cyclo (Pro-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Phe-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Val-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Pro-Phe-D-Trp-4-Amphe-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba-Gaba);

cyclo (Asn-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-NH(CH₂)₄CO);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-β-Ala);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-D-Glu)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Asn-Phe-Phe-D-Trp(F)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp(NO₂)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-Trp(Br)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe(I)-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Tyr(But)-Gaba);

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Tpo-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-MeLeu-Cys)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Phe-Gaba);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-D-Phe-Gaba);

cyclo (Phe-Phe-D-Trp(5F)-Lys-Thr-Phe-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys(Ac)-Thr-Phe-NH-(CH₂)₃-CO);

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba); or

cyclo (Orn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba) or a pharmaceuticallyacceptable salt thereof.

In still another aspect, a method of inhibiting fibrosis in a patientwhich comprises administering to the patient a therapeutically effectiveamount of a somatostatin agonist wherein the somatostatin agonist isD-β-Nal-Cys-Tyr-D-Trp-Lys-Thr-Cys-Thr-NH₂,H-Cys-Phe-Phe-D-Trp-Lys-Thr-Phe-Cys-NH₂,

or D-Phe-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys)-Thr-ol or a pharmaceuticallyacceptable salt thereof. Each of the immediately foregoing methods ispreferred.

In a further aspect, this invention provides a method of inhibitingoverexpression of TGF-β which comprises administering to a subject aneffective amount of somatostatin, somatostatin agonist or apharmaceutically acceptable salt thereof; preferred of this method iswhere a somatostatin agonist is administered; a preferred method of theimmediately foregoing method is wherein the somatostatin agonist has ahigher binding affinity for human somatostatin sub-type receptor 1 thanthe other human somatostatin sub-type receptors, human somatostatinsub-type receptor 2 than the other human somatostatin sub-typereceptors, human somatostatin sub-type receptor 3 than the other humansomatostatin sub-type receptors, human somatostatin sub-type receptor 4than the other human somatostatin sub-type receptors or humansomatostatin sub-type receptor 5 than the other human somatostatinsub-type receptors; or wherein the somatostatin agonist has a higherbinding affinity for two or more of human somatostatin receptorsub-types e.g., 1, 2, 3, 4 and/or 5. Each of the foregoing methods ispreferred.

In another further aspect, this invention provides a method ofinhibiting overexpression of TGF-β which comprises administering to asubject an effective amount of a somatostatin agonist wherein thesomatostatin agonist is

or a pharmaceutically acceptable salt thereof, wherein

A¹ is a D- or L-isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, β-Nal,β-Pal, Trp, Phe, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, or o-X-Phe;

A² is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or p-X-Phe;

A³ is pyridyl-Ala, Trp, Phe, β-Nal, 2,4-dichloro-Phe, pentafluoro-Phe,o-X-Phe, or p-X-Phe;

A⁶ is Val, Ala, Leu, Ile, Nle, Thr, Abu, or Ser;

A⁷ is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or p-X-Phe;

A⁸ is a D- or L-isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, Phe, β-Nal,pyridyl-Ala, Trp, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, oro-X-Phe;

wherein X for each occurrence is independently selected from the groupconsisting of CH₃, Cl, Br, F, OH, OCH₃ and NO₂;

each R₁ and R₂, independently, is H, lower acyl or lower alkyl; and R₃is CH or NH₂; provided that at least one of A¹ and A⁸ and one of A² andA⁷ must be an aromatic amino acid; and further provided that A¹, A², A⁷and A⁸ cannot all be aromatic amino acids.

Also, this invention provides a method of inhibiting overexpression ofTGF-β which comprises administering to a subject an effective amount ofsomatostatin agonist wherein the somatostatin agonist is

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-p-NO₂-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Nal-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂; or

H-D-Phe-Ala-Tyr-D-Trp-Lys-Val-Ala-β-D-Nal-NH₂ or a pharmaceuticallyacceptable salt thereof.

Also, this invention provides a method of inhibiting overexpression ofTGF-β which comprises administering to a subject an effective amount ofsomatostatin agonist wherein the somatostatin agonist is

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-β-Nal-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-OH;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

Gly-Pen-Phe-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Tyr-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-ol;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Trp-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Tro-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Ac-D-Phe-Lys*-Tyr-D-Trp-Lys-Val-Asp-Thr-NH₂, wherein an amide bridge isbetween Lys* and Asp;

Ac-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Bu)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-L-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-L-hArg(CH₂-CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NHEt;

Ac-hArg(CH₃, hexyl)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-hArg(hexyl₂)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Propionyl-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys(iPr)-Thr-Cys-Thr-NH₂;

Ac-D-β-Nal-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Gly-hArg(Et)₂-NH₂;

Ac-D-Lys(iPr)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(Et)₂-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-Cys-Lys-Asn-4-Cl-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Ser-D-Cys-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-p-Cl-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-β-Nal-NH₂;

H-pentafluoro-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Ac-D-β-Nal-Cys-pentafluoro-Phe-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

Ac-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-β-Nal-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Cys-Thr-NH₂;

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-N-Me-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-L-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Ser-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-D-Cl-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-D-Lys-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-Lys-D-Trp-D-Phe);

cyclo (D-Abu-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Tyr);

cyclo (Pro-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Phe-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Val-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Pro-Phe-D-Trp-4-Amphe-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba-Gaba);

cyclo (Asn-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-NH(CH₂)₄CO)

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-β-Ala);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-D-Glu)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Phe-he-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Asn-Phe-Phe-D-Trp(F)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp(NO₂)-Lys-Thr-Phe-Gaba)

cyclo (Asn-Phe-Phe-Trp(Br)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe(I)-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Tyr(But)-Gaba);

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Tpo-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-MeLeu-Cys)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Phe-Gaba);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-D-Phe-Gaba);

cyclo (Phe-Phe-D-Trp(5F)-Lys-Thr-Phe-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys(Ac)-Thr-Phe-NH-(CH₂)₃-CO)

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba); or

cyclo (Orn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba) or a pharmaceuticallyacceptable salt thereof.

Also, this invention provides a method of inhibiting overexpression ofTGF-β which comprises administering to a subject an effective amount ofsomatostatin agonist or a pharmaceutically acceptable salt thereofwherein the somatostatin agonist or a pharmaceutically acceptable saltthereof is D-β-Nal-Cys-Tyr-D-Trp-Lys-Thr-Cys-Thr-NH₂,H-Cys-Phe-Phe-D-Trp-Lys-Thr-Phe-Cys-NH₂;

or D-Phe-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys)-Thr-ol or a pharmaceuticallyacceptable salt thereof. Each of the foregoing methods is preferred.

In still another aspect, this invention provides a method wherein it ispreferred that of each of the methods described above that thesomatostatin agonist is administered parenterally and more preferablythat the somatostatin agonist administered pParenterally is administeredin a sustained release formulation. It is also preferred that of each ofthe methods described above that the somatostatin agonist orpharmaceutically acceptable salt thereof is administered orally ortopically. Each of the foregoing methods is preferred.

Still another aspect of the present invention provides a pharmaceuticalcomposition useful for inhibiting fibrosis in a patient which comprisesa pharmaceutically acceptable carrier and an effective amount ofsomatostatin, somatostatin agonist or a pharmaceutically acceptable saltthereof, preferred of the immediately foregoing pharmaceuticalcomposition is a pharmaceutical composition which comprises asomatostatin agonist or a pharmaceutically acceptable salt thereof.

Still another aspect of the present invention provides a pharmaceuticalcomposition useful for inhibiting overexpression of TGF-β whichcomprises a pharmaceutically acceptable carrier and an effective amountof somatostatin, somatostatin agonist or a pharmaceutically acceptablesalt thereof, preferred of the immediately foregoing pharmaceuticalcomposition is a pharmaceutical composition which comprises asomatostatin agonist or a pharmaceutically acceptable salt thereof.

Definition of “somatostatin agonist” will be defined below. Atherapeutically effective amount depends upon the condition beingtreated, treatment regimen, the route of administration chosen, and thespecific activity of the compound used and ultimately will be decided bythe attending physician or veterinarian. In one embodiment, thesomatostatin agonist is administered to the patient until the fibroticprocess is arrested and/or is reversed. In another embodiment, thesomatostatin agonist is administered for the lifetime of the patient. Instill another embodiment, the somatostatin agonist is administered priorto the event which initiates the fibrotic process (e.g., prior tochemotherapy or exposure to radiation such as in radiation therapy).

Somatostatin or a somatostatin agonist may be injected parenterally,e.g., intravenously, into the bloodstream of the subject being treated.However, it will be readily appreciated by those skilled in the art thatthe route, such as subcutaneous, intramuscular, intraperitoneal,enterally, transdermally, transmucously, sustained released polymercompositions (e.g., a lactic acid polymer or lactic-glycolic acidcopolymer microparticle or implant), profusion, nasal, oral, topical,vaginal, rectal, nasal, sublingual, etc., will vary with the conditionbeing treated and the activity and bioavailability of the somatostatinagonist being used.

The dosage of active ingredient administered in a method of thisinvention may be varied; however, it is necessary that the amount of theactive ingredient be such that a suitable dosage form is obtained. Theselected dosage depends upon the desired therapeutic effect, on theroute of administration, and on the duration of the treatment.Generally, dosage levels of between 0.000001 to 100 mg/kg of body weightdaily are administered to humans and other animals, e.g., mammals.

A preferred dosage range is 0.01 to 5.0 mg/kg of body weight daily whichcan be administered as a single dose or divided into multiple doses.

While it is possible for the somatostatin agonist to be administered asthe pure or substantially pure compound, it may also be presented as apharmaceutical formulation or preparation. The formulations to be usedin the present invention, for both humans and animals, comprise any ofthe somatostatin agonists to be described below, together with one ormore pharmaceutically acceptable carriers thereof, and optionally othertherapeutic ingredients.

The carrier must be “acceptable” in the sense of being compatible withthe active ingredient(s) of the formulation (e.g., capable ofstabilizing peptides) and not deleterious to the subject to be treated.Desirably, the formulation should not include oxidizing agents or othersubstances with which peptides are known to be incompatible. Forexample, somatostatin agonists in the cyclized form (e.g., internalcysteine disulfide bond) are oxidized; thus, the presence of reducingagents as excipients could lead to an opening of the cysteine disulfidebridge. On the other hand, highly oxidative conditions can lead to theformation of cysteine sulfoxide and to the oxidation of tryptophane.Consequently, it is important to carefully select the excipient. pH isanother key factor, and it may be necessary to buffer the product underslightly acidic conditions (pH 5 to 6).

The formulations may conveniently be presented in unit dosage form andmay be prepared by any of the methods well known in the art of pharmacy.All methods include the step of bringing the active ingredient(s) intoassociation with the carrier which constitutes one or more accessoryingredients.

In general, the formulations for tablets or powders are prepared byuniformly and intimately blending the active ingredient with finelydivided solid carriers, and then, if necessary, as in the case oftablets, forming the product into the desired shape and size.

Formulations suitable for parenteral (e.g., intravenous) administration,on the other hand, conveniently comprise sterile aqueous solutions ofthe active ingredient(s). Preferably, the solutions are isotonic withthe blood of the subject to be treated. Such formulations may beconveniently prepared by dissolving active ingredient(s) in a solventcomprising water to produce an aqueous solution, and rendering saidsolution sterile. The formulation may be presented in unit or multi-dosecontainers, for example, sealed ampoules or vials.

Formulations suitable for sustained release parenteral administrations(e.g., biodegradable polymer formulations) are also well known in theart. See, e.g., U.S. Pat. Nos. 3,773,919 and 4,767,628, the teachings ofwhich are incorporated herein by reference, and PCT Publication No. WO94/15587.

Compositions for rectal or vaginal administration are preferablysuppositories which may contain, in addition to the active substance,excipients such as coca butter or a suppository wax.

Compositions for nasal or sublingual administration are also preparedwith standard excipients well known in the art.

For topical administration, they are best used in the form of solutions,creams, salves, lotions, ointments and the like.

The somatostatin or somatostatin agonist may also be administered withknown initiators (e.g., chemotherapeutics) of the fibrotic process toameliorate fibrosis or to prevent the initiation of fibrosis.

Other features and advantages of the invention will be apparent from thefollowing description of the preferred embodiments and from the claims.

Abbreviations

β-Nal=β-naphthylalanine

β-Pal=β-pyridylalanine

hArg(Bu)=N-guanidino-(butyl)-homoarginine

hArg(Et)₂=N,N′-guanidino-(diethyl)-homoarginine

hArg(CH₂CF₃)₂=N,N′-guanidino-bis-(2,2,2,-trifluoroethyl)-homoarginine

hArg(CH₃, hexyl)=N,N′-guanidino-(methyl, hexyl)-homoarginine

Lys(Me)=N^(E)-methyllysine

Lys(iPr)=N-isopropyllysine

AmPhe=aminomethylphenylalanine

AChxAla=aminocyclohexylalanine

Abu=α-aminobutyric acid

Tpo=4-thiaproline

MeLeu=N-methylleucine

Orn=ornithine

Nle=norleucine

Nva=norvaline

Trp(Br)=5-bromo-tryptophan

Trp(F)=5-fluoro-tryptophan

Trp(NO₂)=5-nitro-tryptophan

Gaba=γ-aminobutyric acid

Bmp=β-mercaptopropionyl

Ac=acetyl

Pen=pencillamine.

DETAILED DESCRIPTION OF THE INVENTION

It is believed that one skilled in the art can, based on the descriptionherein, utilize the present invention to its fullest extent. Thefollowing specific embodiments are, therefore, to be construed as merelyillustrative, and not limitative of the remainder of the disclosure inany way whatsoever.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Also, all publications, patentapplications, patents, and other references mentioned herein areincorporated by reference.

The fibrosis which is inhibited can be located in various parts of thebody and can be of a particular kind, for example, the fibrosis may belocated:

in the kidney, for example, fibrosis as observed in glomerulonenephritis(see Yoshioka et al., Lab Invest 1993; 68: 154-63), diabetic nephropathy(see Yamamoto et al., Proc Natl Acad Sci USA 1993;90: 1814-8), allograftrejection (see Shihab et al., Am Soc Nephrol 1993;4: 671, abstract), andHIV nephropathy (see Border et al., J Am Soc Nephrol 1993;4: 675,abstract);

in the liver, for example, cirrhosis (see Castilla et al., N Engl J Med1991;324: 933-940 and Nagy et al., Hepatology 1991;14: 269-73), andveno-occlusive disease (see Anscher et al., N Engl J Med 1993;328:1592-8);

in the lung, for example, idiopathic fibrosis (see Anscher et al., NEngl J Med 1993;328: 1592-8 and Brockelmann et al., Proc Natl Acad SciUSA 1991;88: 6642-6) and autoimmune fibrosis (see Deguchi, Ann Rheum Dis1992;51: 362-5);

in the skin, for example, systemic sclerosis (see Kulozik et al., J ClinInvest 1990;86: 917-22), keloids (see Peltonen et al., J Invest Dermatol1991;97: 240-8), scars (see Ghahary et al., J Lab Clin Med 1993;122:465-73), and eosinophilia-myalgia syndrome (see Varga et al., Ann InternMed 1992;116: 140-7);

in the central nervous system, for example, intraocular fibrosis (seeConner et al., J Clin Invest 1989;83: 1661-6);

in the cardiovascular system, for example, vascular restenosis (seeNikol et al., J Clin Invest 1992;90: 1582-92);

in the nose, for example, nasal polyposis (see Ohno et al., J ClinInvest 1992;89: 1662-8);

in bone or bone marrow (see Harrison's Principles of Internal Medicine,Thirteenth Edition, Volume 2, Chapter 362, pp. 2197-2199; Najean, Y. etal., Leuk Lymphoma, 1996, 22 Suppl 1:111-119; and Reith, J. D. et al.,Am J Srg Pathol, 1996 20(11): 1368-1377);

in an endocrine organ (see Endocrinology, Third Edition, Edited byLeslie J. DeGroot, Vol. 1, pp. 165-177 and pp. 747-751);

and in the gastrointestinal system (see Mizol, T. et al, Cancer Res.,1993 53(1): 183-190; and Tahara, E., J. Cancer Res. Clin. Oncol., 1990,116(2), 121-131).

A fibrotic disorder may be induced by a number of causes including:

chemotherapy, for example, pulmonary fibrosis resulting from bleomycin,chlorambucil, cyclophsphamide, methotrexate, mustine, or procarbazinetreatment (see Key Facts in Oncology by Lilly, Drug Therapy, p.11,1994);

radiation exposure whether accidental or purposeful as in radiationtherapy, for example, interstitial lung disease (ILD) resulting fromradiation (see Cecil Textbook of Medicine, 19^(th) Edition, edited byJames B. Wyngaarden, Lloyd H. Smith, Jr., and J. Claude Bennet, Chapter60, Table 60-5, p. 399, 1992);

environmental or industrial factors or pollutants such as chemicals,fumes, metals, vapors, gases, etc., for example, ILD resulting fromasbestos or coal dust (see Cecil Textbook of Medicine, 19^(th) Edition,edited by James B. Wyngaarden, Lloyd H. Smith, Jr., and J. ClaudeBennet, Chapter 60, Table 60-2, p. 398, 1992);

a drug or a combination of drugs, for example, antibiotics (e.g.penicillins, sulfonamides, etc.), cardiovascular drugs (e.g.hydralazine, beta blockers, etc.), CNS drugs (phenytoin, chlorpromazine,etc.) anti-inflammatory drugs (e.g. gold salts, phenylbutazone, etc.),etc. can cause ILD (see Cecil Textbook of Medicine, 19^(th) Edition,edited by James B. Wyngaarden, Lloyd H. Smith, Jr., and J. ClaudeBennet, Chapter 60, Table 60-4, p. 398, 1992);

an immune reaction disorder, for example, chronic graft-vs-host diseasewith dermal fibrosis, (see Fibrotic Skin Diseases, Editorial, J. Uittoand S. Jimenez, Arch, Dermatol, Vol 126, May 1990, p. 662);

disease states such as aspiration pneumonia which is a known cause ofILD, (see Harrison's Principles of Internal Medicine, Twelfth Edition,Chapter 211, Table 211-1, P 1083) and parasite induced fibrosis (seeWahl, S. M., Kidney Int, 1997, 51(5): 1370-1375); and

wounds, for example, blurt trauma, surgical incisions, battlefieldwounds, etc., as in penetrating injuries of the CNS (see Ann Logan, etal., Brain Research, 587 (1992), 216-225).

Somatostatin and its Agonists

Somatostatin (somatotropin release inhibiting factor or SRIF) has both a14 amino acid isoform (somatostatin-14) and a 28 amino acid isoform(somatostatin-28). See Wilson, J. & Foster, D., Williams Textbook ofEndocrinology, p. 510 (7th ed., 1985). The compound is an inhibitor ofsecretion of the growth hormone and was originally isolated from thehypothalamus. Brazeau et al., Science 179:77 (1973). Native somatostatinhas a very short duration of effect in vivo since it is rapidlyinactivated by endo- and exopeptidase. Many novel analogs have beenprepared in order to enhance the duration of effect, biologicalactivity, and selectivity (e.g., for the particular somatostatinreceptor) of this hormone. Such analogs will be called “somatostatinagonists” herein. Further, compounds that are short peptides modified byorganic moieties and non-peptides, such as organic molecules that do nothave an art-recognized amino acid as part of its structure, that bind tosomatostatin receptor(s) are also within the meaning of “somatostatinagonists”.

Various somatostatin receptors (SSTRs) have been isolated, e.g., SSTR-1,SSTR-2, SSTR-3, SSTR-4, and SSTR-5. Thus, the somatostatin agonist maybe a SSTR-1 agonist, SSTR-2 agonist, SSTR-3 agonist, SSTR-4 agonist of aSSTR-5 agonist. In one embodiment, the somatostatin agonist is an SSTR-2agonist or an SSTR-5 agonist. What is meant by an “SSTR-2 agonist:” oran “SSTR-5 agonist” is a compound which (1) has a high affinity (e.g.,Ki of less than 1 nM or, preferably, of less than 10 nM) for the SSTR-2or SSTR-5, respectively (as defined by the receptor binding assaydescribed below), and (2) inhibits the formation of fibrosis (e.g., asdefined by the biological assay described below) The somatostatinagonist may also be selective for a particular somatostatin receptor,e.g., have a higher binding affinity for a particular somatostatinreceptor subtype. In one embodiment, the somatostatin receptor is anSSTR-2 or SSTR-5 selective agonist.

Somatostatin agonists which can be used to practice the therapeuticmethod of the present invention include, but are not limited to, thosecovered by formulae or those specifically recited in the publicationsset forth below, all of which are hereby incorporated by reference.

EP Application No. 25 164 EU (Inventor: G. Keri);

Van Binst, G. et al. Peptide Research 5:8 (1992);

Horvath, A. et al. Abstract, “Conformations of Somatostatin AnalogsHaving Antitumor Activity”, 22nd European peptide Symposium, Sep. 13-19,1992, Interlaken, Switzerland;

PCT Application WO 91/09056 (1991);

EP Application 0 363 589 A2 (1990);

U.S. Pat. No. 4,904,642 (1990);

U.S. Pat. No. 4,871,717 (1989);

U.S. Pat. No. 4,853,371 (1989);

U.S. Pat. No. 4,725,577 (1988);

U.S. Pat. No. 4,684,620 (1987)

U.S. Pat. No. 4,650,787 (1987);

U.S. Pat. No. 4,603,120 (1986);

U.S. Pat. No. 4,585,755 (1986);

EP Application 0 203 031 A2 (1986);

U.S. Pat. No. 4,522,813 (1985);

U.S. Pat. No. 486,415 (1984);

U.S. Pat. No. 4,485,101 (1984);

U.S. Pat. No. 4,435,385 (1984);

U.S. Pat. No. 4,395,403 (1983);

U.S. Pat. No. 4,369,179 (1983);

U.S. Pat. No. 4,360,516 (1982);

U.S. Pat. No. 4,358,439 (1982);

U.S. Pat. No. 4,328,214 (1982);

U.S. Pat. No. 4,316,890 (1982);

U.S. Pat. No. 4,310,518 (1982);

U.S. Pat. No. 4,291,022 (1981);

U.S. Pat. No. 4,238,481 (1980);

U.S. Pat. No. 4,235,886 (1980);

U.S. Pat. No. 4,224,190 (1980);

U.S. Pat. No. 4,211,693 (1980);

U.S. Pat. No. 4,190,648 (1980);

U.S. Pat. No. 4,146,612 (1979); and

U.S. Pat. No. 4,133,782 (1979).

Examples of somatostatin agonists include, but are not limited to, thefollowing somatostatin analogs and pharmaceutically acceptable saltthereof which are disclosed in the above-cited references:

D-β-Nal-Cys-Tyr-D-Trp-Lys-Thr-Cys-Thr-NH₂ (BIM-23014)

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-β-Nal-NH₂;

D-β-Nal-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-NH₂;

D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Pen-Thr-OH;

D-Phe-Cys-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

Gly-Pen-Phe-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Tyr-D-Trp-Lys-Thr-Cys-Thr-OH;

Phe-Pen-Phe-D-Trp-Lys-Thr-Pen-Thr-OH;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-ol;

H-D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Trp-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Trp-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Ac-D-Phe-Lys*-Tyr-D-Trp-Lys-Val-Asp-Thr-NH₂ (an amide bridge formedbetween Lys* and Asp);

Ac-hArg(Et)₂Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(BU)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-L-hArg(Et)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-L-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys(Me)-Thr-Cys-Thr-NHEt;

Ac-hArg(CH₃, hexyl)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

H-hArg(hexyl)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NHEt;

Ac-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Phe-NH₂;

Propionyl-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys(iPr)-Thr-Cys-Thr-NH₂;

Ac-D-β-Nal-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Gly-hArg(Et)₂-NH₂;

Ac-D-Lys(iPr)-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-D-hArg(CH₂CF₃)₂-D-hArg(CH₂CF₃)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Lys-Thr-Cys-Phe-NH₂;

Ac-D-hArg(Et)₂-D-hArg(Et)₂-Gly-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH₂;

Ac-Cys-Lys-Asn-4-Cl-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Ser-D-Cys-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-p-Cl-Phe-NH₂;

Bmp-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-β-Nal-NH₂;

H-pentafluoro-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-H₂;

Ac-D-β-Nal-Cys-pentafluoro-Phe-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-β-Nal-NH₂;

H-D-β-Nal-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

Ac-D-p-Cl-Phe-Cys-Tyr-D-Trp-Lys-Abu-Cys-Thr-NH₂;

H-D-Phe-Cys-β-Nal-D-Trp-Lys-Val-Cys-Thr-NH₂;

H-D-Phe-Cys-Tyr-D-Trp-Lys-Cys-Thr-NH₂;

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-N-Me-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp=Lys-Thr-N-Me-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-L-Trp-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp(F)-Lys-Thr-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Ser-Phe);

cyclo (Pro-Phe-D-Trp-Lys-Thr-p-Cl-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-D-Lys-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Phe);

cyclo (D-Ala-N-Me-D-Phe-D-Thr-Lys-D-Trp-D-Phe);

cyclo (D-Abu-N-Me-D-Phe-D-Val-Lys-D-Trp-D-Tyr);

cyclo (Pro-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Phe-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-Lys-Val-Phe) ;

cyclo (N-Me-Ala-Tyr-D-Trp-t-4-AchxAla-Thr-Phe);

cyclo (Pro-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Pro-Phe-D-Trp-4-Amphe-Thr-Phe);

cyclo (N-Me-Ala-Tyr-D-Trp-4-Amphe-Thr-Phe);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba-Gaba);

cyclo (Asn-Phe-D-Trp-Lys-Thr-Phe);

cyclo (Asn-Phe-D-Trp-Lys-Thr-Lys-Thr-Phe-NH(CH₂)₄CO);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-β-Ala;

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-D-Glu)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe);

cyclo Phe-Phe-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gly);

cyclo (Asn-Phe-Phe-D-Trp(F)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp(NO₂)-Lys-Thr-Phe-Gaba)

cyclo (Asn-Phe-Phe-Trp(Br)-Lys-Thr-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Phe(I)-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys-Thr-Tyr(But)-Gaba);

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Pro-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-Tpo-Cys)-OH;

cyclo (Bmp-Lys-Asn-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-MeLeu-Cys)-OH;

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-Phe-Gaba);

cyclo (Phe-Phe-D-Trp-Lys-Thr-Phe-D-Phe-Gaba);

cyclo (Phe-Phe-D-Trp(5F)-Lys-Thr-Phe-Phe-Gaba);

cyclo (Asn-Phe-Phe-D-Trp-Lys(Ac)-Thr-Phe-NH-(CH₂)₃-CO);

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Lys-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba);

cyclo (Orn-Phe-Phe-D-Trp-Lys-Thr-Phe-Gaba); and

H-Cys-Phe-Phe-D-Trp-Lys-Thr-Phe-Cys-NH₂(BIM-23268).

Note that for all somatostatin agonists described herein, each aminoacid residue represents the structure of —NH—C(R)H—CO—, in which R isthe side chain (e.g., CH₃ for Ala) except for Thr-ol which means—NH—CH(CH(CH₃)OH)—CH₂—OH and Pro which means prolinyl. Lines betweenamino acid residues represent peptide bonds which join the amino acids.Also, where the amino acid residue is optically active, it is the L-formconfiguration icon that is intended unless D-form is expresslydesignated. A disulfide bridge is formed between two Cys residues;however, it is not shown.

Use of linear somatostatin agonists of the following formula is alsowithin the invention:

or a pharmaceutically acceptable salt thereof, wherein

A¹ is a D- or L- isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, β-Nal,β-Pal, Trp, Phe, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, or o-X-Phe;

A² is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or p-X-Phe;

A³ is pyridyl-Ala, Trp, Phe, β-Nal, 2,4-dichloro-Phe, pentafluoro-Phe,o-X-Phe, or p-X-Phe;

A⁶ is Val, Ala, Leu, Ile, Nle, Thr, Abu, or Ser;

A⁷ is Ala, Leu, Ile, Val, Nle, Phe, β-Nal, pyridyl-Ala, Trp,2,4-dichloro-Phe, pentafluoro-Phe, o-X-Phe, or o-X-Phe;

A⁸ is a D- or L-isomer of Ala, Leu, Ile, Val, Nle, Thr, Ser, Phe, β-Nal,pyridyl-Ala, Trp, 2,4-dichloro-Phe, pentafluoro-Phe, p-X-Phe, oro-X-Phe;

each R₁ and R₂, independently, is H, lower acyl or lower alkyl; and R₃is OH or NH₂; provided that at least one of A¹ and A⁸ and one of A² andA⁷ must be an aromatic amino acid; and further provided that A¹, A², A⁷and A⁸ cannot all be aromatic amino acids.

Examples of linear agonists to be used in the method of this inventioninclude:

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-p-NO₂-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Nal-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-NH₂;

H-D-Phe-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂;

H-D-Phe-p-chloro-Phe-Tyr-D-Trp-Lys-Val-Phe-Thr-NH₂; and

H-D-Phe-Ala-Tyr-D-Trp-Lys-Val-Val-Ala-β-D-Nal-NH₂ or a pharmaceuticallyacceptable salt thereof.

If desired, one or more chemical moieties, e.g., a sugar derivative,mono- or poly-hydroxy C₂₋₁₂ alkyl, mono or poly-hydroxy C₂₋₁₂ acylgroups, or a piperazine derivative, can be attached to the somatostatinagonist, e.g., to the N-terminus amino acid. See PCT Application WO88/02756, European Application 0 329 295, and PCT Application No. WO94/04752. An example of a somatostatin agonists which contain N-terminalchemical substitutions are:

(BIM-23197) or a pharmaceutically acceptable salt thereof.

Synthesis of Somatostatin Agonists

The methods for synthesizing somatostatin agonists are well documentedand are within the ability of a person of ordinary skill in the art, forexample, as illustrated in the U.S. Patents and other references citedhereinabove.

Synthesis of short amino acid sequences is well established in thepeptide art. For example, synthesis ofD-Nal-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH₂, described above, can besynthesized by following the protocol set forth in U.S. Pat. No.4,853,371 and synthesis of H-D-Phe-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-NH₂,described above, can be achieved by following the protocol set forth inExample I of European Patent Application 0 395 417 A1. The synthesis ofsomatostatin agonists with a substituted N-terminus can be achieved, forexample, by following the protocol set forth in WO 88/02756, EuropeanPat. Application No. 0 329 295, and PCT Publication No. WO 94/04752.

Somatostatin Receptor Binding Assays

The human SSTR-1, SSTR-2, SSTR-3, SSTR-4, and SSTR-5 cDNA clones havebeen described (SSTR-1 and SSTR-2 in Yamada, Y., et al., Proc. Natl.Acad. Sci. USA., 89:251-255 (1992); SSTR-3 in Yamada, et al., Mol.Endocrinol. 6:2136-2142 (1993); and SSTR-4 and SSTR-5 in Yamada, et al.,Biochem. Biophys. Res. Commun. 195:844-852 (1993)) and are alsoavailable from American Type Culture Collection (ATCC, Rockville, Md.)(ATCC Nos. 79044 (SSTR-1), 79046 (SSTR-2), and 79048 (SSTR-3)). Based onthe restriction endonuclease maps, the entire coding region of each SSTRcDNA may be excised by suitable restriction endonuclease digestion(Maniatis, T., et al., Molecular Cloning—A Laboratory Manual, CSHL,1982), Restriction endonucleases are available from New England Biolabs(Beverly, Mass.). This cDNA fragment was inserted into the mammalianexpression vector, pCMV (Russell, D., et al., J. Biol. Chem.,264:822-8229 1989)), using standard molecular biology techniques (seee.g., Maniatis, T., et al., Molecular Cloning, -A Laboratory Manual,Cold Spring Harbor Laboratory, 1982) to produce the expression plasmid,pCMV-human SSTR-1 through pCMV-human SSTR-5. Other mammalian expressionvectors include pcDNA1/Amp (Invitrogen, Sandlesy, Calif.). Theexpression plasmids were introduced into the suitable bacterial host, E.Coli HB101 (Stratagene, La Jolla, Calif.) and plasmid DNAs, fortransfection, were prepared on Cesium Chloride gradients.

CHO-K1 (ovary, Chinese hamster) cells were obtained from ATCC (ATCC No.CCL 61). The cells were grown and maintained in Ham's F12 media (GibcoBRL, Grand Island, N.Y.) supplemented with 10% fetal bovine serum understandard tissue culture conditions. For transfection, the cells wereseeded at a density 1×10⁶/60-cm plate (Baxter Scientific Products, McGawPark, Ill.). DNA mediated transfection was carried out using the calciumphosphate co-precipitation method (Ausubel, F. M., et al., CurrentProtocols in Molecular Biology, John Wiley & Sons, 1987). The plasmidpRSV-neo (ATCC; ATCC No. 37198) was included as a selectable marker at{fraction (1/10)} the concentration of the expression plasmid. CHO-K1clonal cell lines that have stably inherited the transfected DNA wereselected for growth in Ham's F12 media containing 10% fetal bovine serumand 0.5 mg/ml of G418 (Sigma). The cells were ring-cloned and expandedin the same media for analysis.

Expression of the human SSTR-1 through SSTR-5 receptors in the CHO-K1cells were detected by Northern blot analysis of total RNA prepared fromthe cells (Sambrook, J. E., et al., Molecular Cloning—A LaboratoryManual, Ed. 2., Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y.,1989) and by receptor binding using [¹²⁵I-Tyr¹¹]somatostatin-14 as aligand. Transfected cell lines expressing the human SSTR receptors wereclonally expanded in culture and used in the following SSTR bindingprotocol.

Crude membranes were prepared by homogenization of the transfected cellsin 20 ml of ice-cold 50 mM Tris-HCl with a tissue homogenizer setting 6,15 sec). Buffer was added to obtain a final volume of 40 ml, and thehomogenate was centrifuged in a Sorval® SS-34 rotor (Sorval, Newtown,Conn.) at 39,000 g for 10 min at 0-4° C. The resulting supernatant wasdecanted and discarded. The pellet was rehomogenized in ice-cold buffer,diluted, and centrifuged as before. The final pellet was resuspended inthe 10 mM Tris HCl and held on ice for the receptor binding assay.

Aliquots of the membrane preparation were incubated for 30 min at 30° C.with 0.05 nM [¹²⁵I-Tyr¹¹]somatostatin-14 (2000 Ci/mmol; Amersham Corp.,Arlington Heights, Ill.) in 50 mM HEPES (pH 7.4) containing a testsomatostatin agonist of various concentrations (e.g., 10⁻¹¹ to 10⁻⁶), 10mg/ml bovine serum albumin (fraction V) (Sigma Chemical Co., St. Louis,Mo.), MgCl₂ (5 mM), Trasylol (also known as aprotinin) (Sigma ChemicalCo.) (200 KIU ml), bacitracin (Sigma Chemical Co.) (0.02 mg/ml), andphenylmethylsulphonyl fluoride (Sigma Chemical Co.) (0.02 mg/ml). Thefinal assay volume was 0.3 ml. The incubations were terminated by rapidfiltration through GF/C filters (pre-soaked in 0.3% polyethylenimine for30 min) using a Brandel filtration manifold (Brandel Research andDevelopment Co., Gaithersburg, Md.). Each tube and filter were thenwashed three times with 5 ml aliquots of ice-cold buffer. Specificbinding was defined as the total [¹²⁵I-Tyr¹¹] somatostatin-14 boundminus that bound in the presence of 1000 nM of somatostatin-14. The Kivalues for the tested somatostatin agonists were calculated by using thefollowing formula: Ki=IC₅₀/[1+(LC/LEC)] where IC₅₀ is the concentrationof test somatostatin agonist required to inhibit 50 percent of thespecific binding of the radioligand [¹²⁵I-Tyr¹¹]somatostatin-14, LC isthe concentration of the radioligand (0.05 nM), and LEC is theequilibrium dissociation constant of the radioligand (0.16 nM). The Kivalues (nM) for the tested somatostatin agonists are shown in Table I.

TABLE I hSSTR-1 hSSTR-2 hSSTR-3 hSSTR-4 hSSTR-5 Somato- 2.256 0.71 1.4321.768 0.883 statin-14 Somato 2.382 0.57 1.021 7.93 0.383 statin-28BIM-23014 2414 1.10 121 1826 5.21 BIM-23190 5210 0.47 2154 7537 11.1BIM-23197 6016 0.09 26.8 3897 9.81 BIM-23268 12.27 6.84 62 19.96 0.38

Inhibition of Fibrosis

The somatostatin agonists may be tested for their ability to inhibitfibrosis.

(a) Demonstration of Anti-Fibrotic Activity In vitro

Rats are injected either with anti-thymocyte serum (ATS) (see S. Okuoaet al., J. Clin. Invest., Vol. 86, 1990, pp. 453-462) to induceglomerulonephritis or with phosphate buffered saline (PBS) to serve ascontrols. Six days later, the kidneys are removed, and the glomeruli areisolated and placed in culture for 72 hours. Culture conditions consistof 2000 glomeruli/well in a 1 ml volume of serum-free RPMI 1640 (withinsulin supplementation) (Gibco, Gaithersburg, Md.). Test somatostatinor somatostatin agonists are added at the time of culture. Thesupernatant from the cultures is collected and stored at −70° C. untilassayed to determine the concentration of collagen I, transforminggrowth factor β-1(TGFβ-1, fibronectin containing an extra domain A(fibronectin EDA+), and plasminogen activator inhibitor I (PAI-I), asmarkers of fibrotic activity. In addition, individual glomeruli areexamined by immunofluorescent staining and scored for relevant matrixproteins. Values were compared between PBS-treated, negative fibroticcontrol glomeruli; ATS-treated, non-drug treated, positive fibroticcontrol glomeruli; and the ATS-treated, drug treated, fibrotic glomerulito determine the degree to which the fibrotic process is inhibited bysomatostatin or the somatostatin agonists.

(b) Demonstration of Anti-Fibrotic Activity In vivo

Rats are injected either with anti-thymocyte serum (ATS) to induceglomerulonephritis or with phosphate buffered saline (PBS) as a control.One hour later, treatment is initiated with somatostatin or asomatostatin agonist. Somatostatin or the somatostatin agonist areadministered subcutaneously twice per day for 5 days. On day 5 the ratsare placed in metabolic cages, and 24 hour urine is collected todetermine protein content. On day 6, the kidneys are removed, and tissuesamples are either placed in formalin or frozen for histologicalevaluation. Glomeruli are isolated from the remaining tissue and areplaced in culture for 72 hours. Culture conditions consisted of 2000glomeruli/well in a 1 ml volume of serum free RPMI 1640 (with insulinsupplementation). The supernatant from the cultures are collected andstored at −70° C. until assayed to determine the concentration ofcollagen I, transforming growth factor β-1 (TGFβ-1), fibronectincontaining an extra domain A (fibronectin EDA+), and plasminogenactivator inhibitor I (PAI1) as markers of fibrotic activity. Thepresence of matrix proteins is measured via immunofluorescent stainingof frozen kidney sections with antibodies to matrix proteins induced byTGFβ-1 such as fibronectin EDA+, collagen I, PAI1, and tenasin. From thecultured isolated glomeruli direct measurements of TGFβ-1, PAI1, andfibronectin secreted into the culture supernatant can be determined viaELISAs enzyme-linked immunoabsorbent assay). Glomeruli from samples ineach group can be used to extract mRNA and the message levels forTGFβ-1, GADPH, collagen I, collagen III, fibronectin, and PAI1determined by Northern analysis. As an indicator of gross histologicalchanges, PAS (periodic acid-Schiff) stained paraffin sections are gradedon the basis of their pathological matrix scores. Values are comparedbetween PBS-treated, negative fibrotic control animals; ATS-treated,non-drug created, positive fibrotic control animals; and theATS-treated, drug-treated animals to determine the degree to which thefibrotic process is inhibited by somatostatin or the somatostatinagonist.

OTHER EMBODIMENTS

The foregoing description has been limited to specific embodiments ofthis invention. It will be apparent, however, that variations andmodifications may be made to the invention, with the attainment of someor all of the advantages of the invention. Such embodiments are alsowithin the scope of the following claims.

What is claimed is:
 1. A method of inhibiting fibrsois in a patientsuffering from fibrosis said method comprising administering atherapeutically effective amount of somatostatin or a somatostatinagonist to said patient, provided said fibrosis is not in the kidney, inthe lung, in the liver, in the skin, of the central nervous system, inbone or bone marrow, in the cardiovascular system, in an endocrineorgan, or in the gastro-intestinal system, and further provided thatsaid fibrosis is not periportal fibrosis.
 2. The method of claim 1,wherein said method comprises administering a therapeutically effectiveamount of a somatostatin agonist to said patient.